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Roadster Foundry mobile charging kit

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TEG

Teslafanatic
Moderator
Aug 20, 2006
22,101
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As many have heard, Martin Eberhard designed and built himself a mobile charging kit that is more flexible than what the "factory" currently offers. When others saw what he had created they decided they would like to make something similar.
Bill Arnett provided some pictures that Doug posted here:
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EVcomponents has announced that they plan to sell them, hopefully starting next month.

From what I know, the production rate isn't yet known, and parts supplies for the kit still need to get worked out, so there could end up being a wait list or delays depending on what happens.

I got a chance to look at the manual for the kit, and thought it might be helpful to pass along some observations of what the kit can and cannot do.

The EVcomponents link currently includes this:
Coming July 2009
Roadster Mobile Charging cable and connector.
Comes with adapters for recharging a Roadster at 12 amps, 24 amps or 40 amps.
The Roadster Foundry Mobile Charger allows you to charge a Tesla Roadster at standard electrical outlets, including the following:

  1. NEMA 5-15 120V 15A
  2. NEMA 10-30 208V-240V 30A
  3. NEMA 14-30 208V-240V 30A
  4. NEMA 10-50 208V-240V 50A
  5. NEMA 14-50 208V-240V 50A
So, basically you have a choice of stubby adapter cables that go from the socket you have found to the "logic box" which then feeds a 20 foot long cable to the Roadster connector. The "logic box" will "know" what source cable you have inserted, and in turn will tell the Roadster what "default" charge rate to pull. In some cases you may need to adjust the charge rate manually from the VDS if the circuit breaker feeding the circuit is too low for the default charge rate.

See also:
NEMA 14-50: How much current can you pull?
Campground Charging
Charging the Roadster
Road trips

Note, I have no idea if Tesla has any kind of 'stance' with regards to warranty impact from using this kit.
 
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Going through the different socket/cable options, here are some notes:

1. NEMA 5-15 120V 15A

NEMA-5-15R-outlet.gif


This is the "Standard" USA household outlet. It will draw 120V@12A just like a Tesla MC120 would.
 
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2. NEMA 10-30 208V-240V 30A

CW38B-BOX-EA-2.jpg


This would plug into a common home dryer socket. The kit would tell the Roadster to take 240V@24A.

Note, don't mix this up with a campground TT-30 120V trailer socket. The kit's NEMA 10-30 plug has one L shaped pin, and the socket must have a L shaped hole in the same position. Don't try to force the plug into a socket with a round hole there. This plug is NOT meant to be used at a campground or boat dock.
 
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3. Nema 14-30 208v-240v 30a

220v30a4p_thumb155_crop.jpg
DRYER-4-WIRE-OUTLET.JPG


This would be to plug into household dryer outlets in newer homes that have a grounding pin. The kit would tell the Roadster to try 240V@24A
 
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4. Nema 10-50 208v-240v 50a

u245753.jpg


This is typically used for home ovens and electric stoves. It would be unusual to find one in a public place, but should you find one, the Roadster will be told that it can try to draw 240V@40A
 
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5. NEMA 14-50 208V-240V 50A

Cooper_Wiring_Devices_Nema_14-50_5754N.jpg


This one is used in a bunch of different places. The Tesla MC240 uses this, but takes a conservative approach of only using up to 30amps. The Roadster Foundry kits tells the Roadster that it should be OK to draw 240V@40A but this isn't always appropriate. Some home stoves, dryers or other large electric appliances may use this, but only offer a 40amp breaker (32amp max allowed draw), some RV/campground adapter cables may provide this socket but offer far less current capability. Some adapter kits used to convert a public EV charger (e.g.: Avcon) to NEMA14-50 may also have lower current capability and charging at 24amps may be most appropriate there. Even if the breaker doesn't trip, some installations may have wiring that is not rated for 40amp current load, so it is really best to research the true capability of each NEMA 14-50 socket you find to know the max current capability. (Just because it turns on doesn't mean it is OK - it could cause something to overheat if you pull more current than the wiring was designed to handle).

Related topic: NEMA 14-50: How much current can you pull?
 
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Suggestions for future improvements:


  • A different version of the NEMA 5-15 cable that tells the Roadster that 120V@16A is OK. This would be for cases where you know the socket has a 20A breaker, and nothing else is plugged into the circuit.
  • A campground TT-30 cable that tells the kit to let the Roadster know that it could use 120V@24A
  • A different version of the NEMA 14-50 plug that tells the Roadster 240V@24A (instead of @40A) to be used when connecting to the EAA Avcon adapter box. (Modifying the EAA box to have a 14-30 could also suffice).
Note, the logic box has a small limit to how many different cable types it can be trained to detect. Adding more types might mean a redesign, or sacrificing one of the existing cable types to make room for something different.
 
Suggestions for future improvements:

I'm still trying to get up to speed here so apologies in advance.

What about measuring? Either carry an Ampmeter meter that can measure the available current and be able to program it into the box (or of course the car) or build the meter into the box or car so it automatically determines the maximum safe draw and applies that amount.

Is it one of those things where you have to have a load to test it and if you drive up to a charger and test it with different loads then you might blow the breaker? Then that breaker is in a panel somewhere that no one at the mall has access too?

The other problem seems to be that with hall effect clamp meter
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you would have to get open access to the cables to measure the current flow.

Still though, it seems like someone would have figured this out by now.
 
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Is it one of those things where you have to have a load to test it and if you drive up to a charger and test it with different loads then you might blow the breaker? Then that breaker is in a panel somewhere that no one at the mall has access too?

Yes, that is a real concern. So, if possible, understand what wiring, breakers and over-current protection lives behind the socket you are about to use. If you can't find that out then it is probably best to draw a conservative amount (which is usually 240V@24A). I would think it best to leave the "learning by probing" to some team of experts (e.g., the EAA folks) who then will (hopefully) label things as needed. The EAA Avcon box should probably have a label next to the NEMA 14-50 saying "not for more than 30 amps".

I wish those RV adapter cables had clear warning labels on them.
Like the "cheater" and "dogbone" adapters should say something like "not intended for use with 240V devices" as they are meant to provide two paths of 120V service at < 30amps each.

Those in the know think so much of this stuff is obvious, but for the non-electrician out there, seeing a NEMA14-50 socket with "50 amps" stamped right on it can be misleading.
Just because the plug fits in the socket doesn't guarantee it is going to work.
 
Tesla's stance on Martin's Charger

Note, I have no idea if Tesla has any kind of 'stance' with regards to warranty impact from using this kit.

It just so happens that I got a call from Ted Merendino from Tesla today. He was confirming my options selection (and telling me that they think they can ship my Roadster in mid-August rather than in October/November as originally promised(!)) Anyway, in my options I didn't select a Tesla charger other than the MC120, and he asked me about it. I told him that my plan is to buy one of Martin's chargers, and he didn't say anything about it voiding the warranty or anything like that. All he said was that the HPC had the advantage of being able to automatically reset after a power surge, which might matter if the car's stuck on the charger for many weeks without anyone checking it.

However, since I have two houses, he agreed that a 240v mobile charger is the way to go anyway.

So, that's hardly official confirmation that it's OK, but they do know about it and didn't really try to discourage me from buying it or issue any serious warnings.
 
It just so happens that I got a call from Ted Merendino from Tesla today. He was confirming my options selection (and telling me that they think they can ship my Roadster in mid-August rather than in October/November as originally promised(!)) Anyway, in my options I didn't select a Tesla charger other than the MC120, and he asked me about it. I told him that my plan is to buy one of Martin's chargers, and he didn't say anything about it voiding the warranty or anything like that. All he said was that the HPC had the advantage of being able to automatically reset after a power surge, which might matter if the car's stuck on the charger for many weeks without anyone checking it.

However, since I have two houses, he agreed that a 240v mobile charger is the way to go anyway.

So, that's hardly official confirmation that it's OK, but they do know about it and didn't really try to discourage me from buying it or issue any serious warnings.

So, just to be clear, Ted said a 240v would be fine, and you are getting Martin's charger instead of that (since it's the same thing, but better and more flexible). Right?
 
...All he said was that the HPC had the advantage of being able to automatically reset after a power surge, which might matter if the car's stuck on the charger for many weeks without anyone checking it...

Note, as far as I know, all of Tesla's factory chargers have GFCI, but the Martin designed Roadster Foundry kit only uses GFCI on the NEMA 5-15 plug. If you are charging at 240V with the Roadster Foundry kit then there is no GFCI built in. So... the so-called advantage of "self reset" on the new Tesla HPC is sort of a "moot point" with the Roadster Foundry kit.

Note, this Roadster Foundry kit isn't really in any kind of production yet. I think Martin has only made a few, and hopes to have EVcomponents take over. I don't think either of them are doing this as a profit business, more as a favor to fellow Roadster owners. So, it might be premature to make plans to use this as your exclusive charger. You could end up waiting a while. Hopefully James chimes in, but you may need to provide a MC120 that willl be exchanged as part of the kit purchase. There are some unanswered questions as to how this will get from Martin's prototypes to something in limited production at EVcomponents. I would stay tuned, and consider other options in the short term.
 
So, just to be clear, Ted said a 240v would be fine, and you are getting Martin's charger instead of that (since it's the same thing, but better and more flexible). Right?

Yes. Ted said that given that I have 2 houses, a 240v mobile charger made more sense than an HPC, and he seemed to be OK with Martin's because it was more flexible and cheaper. He didn't realize that they were going into regular production, though.

He did want to make sure that I wasn't planning on using the 120v charger exclusively.
 
...He didn't realize that they were going into regular production, though...

Just because EVcomponents has a "coming soon" on their web site, don't get too excited just yet. It is yet to be seen what sort of volume "regular production" means. I don't know how many people they will have working on this, how hard it will be to get the parts, and what sort of lead time they will have on the parts. Hopefully they can make all everyone wants quickly, but I wouldn't count on it as a sure thing just yet.

Apparently some other people approached Martin before about making these and then backed out. It turns out to be harder than it first appears to actually get these kits constructed.
 
Apparently some other people approached Martin before about making these and then backed out. It turns out to be harder than it first appears to actually get these kits constructed.

If I can't get one soon enough, I can always just buy the MC240 from Tesla. I've still got a few months at least.
 
Aftermarket Business Revs Up for Tesla Roadster - Includes a Strange Bedfellow

When asked how it reacted to Eberhard's new sideline by Inside Line, Tesla Motors spokeswoman Rachel Konrad responded in an e-mail: "Tesla has delivered more than 500 cars to customers and is delivering more every day, so it's only natural to expect a proliferation of related aftermarket parts. The ecosystem for Evs is rapidly growing — a great thing for consumers, the auto industry and the environment."
 
He is not even the first. There is an owner making up front plate brackets and an Iphone mounting bracket.

There are a few Lotus bits that showed up on cars at the rally.

Al and Ed's has a full color brochure featuring all the work on Dr Taras' car.

Accessories thread?
 
Tesla does not make this package,

Tango does.
CHRIS: Is the Avcon system designed so that it can be plugged directly into a standard home or dyer outlet or would a Tango owner need to install a specific type of charging system in the home?

RICK: Since the Avcon is a conductive charging connector, we use it so that the existing charging infrastructure in California and Arizona can be used. A cord is supplied with the Tango that has an Avcon connector on one end to attach to the car and a 14-50 plug on the other end. This is the plug used in RV parks. We also supply at least 3 pigtails so that the 14-50 plug can be plugged into it at one end and the other is a customer-selected assortment of plugs. We supplied a 110V standard, a 220v dryer plug, and a welder plug with the car. For close to $10 you can put any other plug you want. The charger has an amperage adjustment and an AC ammeter so you can set the amperage to the maximum that your circuit breaker can withstand. Usually 15 amps for 110, and 40 amps for 220. Any voltage is acceptable, without adjustment ranging from 100 to 250 VAC or DC which is useful for solar installations.